Apparatus and method for treating grains and legumes

ABSTRACT

A machine for heat treating granular, organic materials and primarily, though not exclusively, intended for such treatment of whole soybeans and corn, comprising a drum mounted for rotation within an elongated receiver, the drum being constructed and arranged to define, with a portion at the peripheral wall of the receiver, a peripheral series of pockets travelling with the drum, a fluid-fuel burner associated with the receiver and arranged to discharge, into a portion of the receiver in which the pockets are outwardly open, a longutidinally-extending, peripherally-restricted wall of flame impinging on said drum, the burner including flame guard means constructed and arranged to establish such a wall of flame, and means for driving the drum to cause such granular material to be moved rapidly and intermittently through the flame wall and in close proximity to the source of the infra-red energy.

United States Patent Skelton et a1.

[451 Aug. 1, 1972 [72] Inventors: Robert F. Skelton, Bluffton; Harry Truax, Mooresville, both of Ind.

[73] Assignee: Mix-Mill, lnc., Bluffton, Ind.

[22] Filed: April 13, 1970 [21] Appl. No.: 27,896

[52] 11.8. C1. ..99/235 R, 99/2 [51] Int. Cl. ..A23k 1/00 Field of Search ..99/236, 234, 235, 237, 238, 99/2; 34/48, 132, 134; 110/8, 18; 118/19, 21;

3,407,511 10/1968 Camm ..263/33 X Primary Examiner-Edward L. Roberts Assistant Examiner-Arthur 0. Henderson Attorney-Hume, Clement, Hume & Lee, Ltd.

[57 ABSTRACT A machine for heat treating granular, organic materials and primarily, though not exclusively, intended for such treatment of whole soybeans and corn, comprising a drum mounted for rotation within an elongated receiver, the drum being constructed and arranged to define, with a portion at the peripheral wall of the receiver, a peripheral series of pockets travelling with the drum, a fluid-fuel burner associated with the receiver and arranged to discharge, into a portion of the receiver in which the pockets are outwardly open, a longutidinally-extending, peripherally-restricted wall of flame impinging on said drum, the burner including flame guard means constructed and arranged to establish such a wall of flame, and means for driving the drum to cause such granular material to be moved rapidly and intermittently through the flame wall and in close proximity to the source of the infra-red ener- 18 Claims, 5 Drawing Figures PATENTEDAUB 1 I972 INVENTORS ROBERT F. SKELTON HARRY TRUAX you; q i ozfi APPARATUS AND METHOD FOR TREATING GRAINS AND LEGUMES The present invention is concerned with the treatment of granular, organic materials, including certain legumes and grains, to improve their flavor and nutritional characteristics. The primary object of the present invention, therefore, is analogous to the objects of the inventions disclosed and claimed in US. Pat. Nos. 3,343,961 issued Sept. 26, 1967 and 3,368,475 issued Feb. l3, 1968, the present invention being an improvement upon that disclosed and claimed in the above identified patents.

It has been discovered that, contrary to the burden of the disclosure ofthe above-identified prior patents, improved results are achieved if the granular, organic material, such as soybeans and corn in particular, is subjected to direct .flame impingement, as well as to infra-red energy, for very brief, successive periods of time; and the present invention is directed primarily to the provision of apparatus through which such a treatment can be advantageously accomplished as well as a method for such treatment.

To the accomplishment of the above and related objects, our invention may be embodied in the forms illustrated in the accompanying drawings and in the method described herein, attention being called to the fact, however, that the drawings and description are illustrative only, and that change may be made in the specific constructions and method illustrated and described, so long as the scope of the appended claims is not violated.

FIG. 1 is a somewhat diagrammatic side elevation of apparatus constructed in accordance with the present invention;

FIG. 2 is a section taken substantially on the line 2- 2 of FIG. 1 and drawn to an enlarged scale;

FIG. 3 is a fragmentary section, drawn to a further enlarged scale, and illustrating burner details;

FIG. 4 is a view similar to FIG. 3 but illustrating a modified flame guard; and

FIG. 5 is a view similar to FIG. 2 but showing a modified form of apparatus.

The apparatus of the present application has been designed, and has been used, primarily for the treatment of whole, unextracted soybeans and in the following specification it will be discussed in reference to soybeans. However, in experimental operations, to be described hereinafter, it has been found to be beneficial in the treatment of shelled corn and it is believed that it may well be useful in the treatment of other legumes, grains, seeds, nuts and similar discrete or granular organic materials. The inherent characteristics of the machine are such that the individual granules of the material being treated are moved repeatedly, and for very short intermittent periods, through a region in which they are subjected to direct flame impingement, bombardment with infra-red energy and heat by convection, the granules being carried, after each such brief period, through a region of much lower temperature and generally out of the field of infra-red energy, for a much longer period, whereby burning or overcooking of the granules is obviated.

Referring more particularly to the drawings and specifically to FIGS. 1-3 thereof, it will be seen that we have somewhat diagrammatically illustrated a suitable base upon which is supported a receiver indicated generally by the reference numeral 11, said receiver being generally in the form of a substantially closed, elongated housing or trough which may be suitably encased in heat-insulating material indicated at 12.

As is most clearly shown in FIG. 2, the receiver 11 may advantageously comprise a lower portion 13 and an upper portion 14. Preferably, the cross sectional contour of the portion 13 is is an arc while the cross sectional contour of the portion 14 is generally elliptical. An inlet hopper 15 opens into the received adjacent one end thereof and the opposite end 16 of the receiver is open to deliver treated granular material to discharge means 17 which may be of any desired character. Alternatively, the treated granular material may be permitted to fall from the receiver end 16 into a suitable storage or delivery container, or directly onto the floor. Preferably, the receiver 11 will be slightly inclined downwardly from its inlet end to encourage movement of the granular material, during treatment, at a desired rate from the region of the hopper 15 and to and through the open end 16 of said receiver.

A drum 18 is mounted within the receiver for rotation about its axis 19 which is preferably concentric with the arc of the receiver portion 13 and said drum is provided with a multiplicity of outwardly-extending fins 20 which are preferably uniformly peripherally spaced about the external surface of said drum. There is k inch clearance between the radially outer edge of each fin and the inside surface of the arc of receiver portion 13. This clearance serves to prevent cracking of beans by the fins. In spite of this clearance, all beans move through the receiver because there is a mass movement of beans from the inlet end of the receiver to its outlet end. The receiver, however, will usually never empty because of this clearance. That is, individual beans can lie dormant on the bottom of the receiver.

A prime mover, which may be an electric motor, is suitably supported on the machine base and is indicated at 21, said prime mover driving a shaft 22 which, in turn, is connected as at 23 to drive the drum 18. Obviously, a suitable reduction gear (not shown) may be introduced between the prime mover 21 and the drum 18.

A novel form of burner is indicated generally by the reference numeral 24. As shown, said burner comprises a conduit 25 arranged longitudinally of the receiver 11 and formed with a plurality of longitudinally-spaced ports 26 arranged to open toward the interior of the receiver 11, the conduit 25 being substantially coextensive with said receiver. A blower 27 is connected to be driven by the prime mover 21 and to draw atmospheric air through an inlet 28 whose effective area may be varied by suitable means (not shown). A fluid-fuel supply line is indicated at 29 and preferably, as shown, is arranged to deliver fluid fuel into the airstream at a rate determined by manipulation of conventional flowcontrol means (not shown). The'combustible mixture of fuel and air is delivered by the blower 27 through a manifold 30 to one end of the conduit 25, whereby that mixture will be ejected, through the ports 26, toward the drum 18. Suitable ignition means such as a sparking plug (not shown) may be provided for igniting the combustible mixture as it is so ejected.

Flame guard means indicated generally by the reference numeral 31 is interposed between the ports 26 and the drum 18. As shown, such flame guard means may comprise Z-shaped brackets 32 and 33 secured to the conduit 25 and longitudinally substantially coextensive with the series of ports 26. These brackets 32, 33 rest on the receiver portion 14. The bracket 32 is formed with a lip 34 extending toward the similar, but allochirally arranged lip 35 of the bracket 33, the distal ends of said lips being narrowly laterally spaced apart to define a slit or laterally-restricted opening 36 through which the flame 37 is ejected under pressure in a longitudinally-extending, substantially continuous, laterally narrow wall. Desirably, the burner system is operated at such a pressure that the flame wall 37 will impinge upon that peripherally-narrow region of the external surface of the drum 18 which is, at any instant, in direct'registry with the opening 36.

The products of combustion, as well as any vapors driven off from the material under treatment, will be emitted through an exhaust stack 38 which may, of course, be equipped with any desired type of wasterecovery or antipollution equipment (not shown).

In operation, the burner 24 will be ignited and the drum :18 will be set into continuous rotation in the direction of the arrow seen in FIG. 2. As the flame 37 is emitted through the opening 36, it heats the lips 34 and 35 and, to some extent, the entire bodies of the brackets 32 and 33. Within a short time, the lips 34 and 35 will approach, and sometimes achieve, incandescence, whereby they become a source of infra-red energy. The surface of the drum 18, and the fins 20, likewise will be heated, but to a lesser degree.

Now, soybeans (or other granular, organic material) will be charged into the machine through the hopper to fall into the outwardly-opening pockets defined between the adjacent fins 20. At the outset, all of the beans in any one pocket will be disposed at the inlet end of the drum; but, because of the inclination of the axis of the drum and of the floor of the receiver, the

beans in any one pocket will tend to travel from right to left as viewed in FIG. 1 as rotation of the drum continues. Obviously, beans delivered to any pocket will first be carried in a counterclockwise'direction down into and through the lower portion 13 of the receiver. As the cooperating fins of any one pocket begin to enter the upper section of the receiver, the receiver wall retreats from the path of the fin edges to open the pocket defined thereby outwardly and to permit the beans in that pocket to be thrown, in a generally tangential direction, into close proximity to the flame guard means 31 and thus to be cascaded through the wall or curtain of flame being emitted from the slit 36 to impinge upon the external surface of the drum 18. Thus, the beans are exposed, for very brief periods, to flame impingement, direct and close infra-red energy and to heat by convection, as well as to heat by conduction. During the instantaneous passage of an individual bean through the flame curtain, of course, its external surface is subjected to extremely high temperature whereby it is found that, occasionally, a bean jacket will actually ignite; but any such fire is very promptly extinguished as the bean falls back into a pocket and is carried into proximity with the wall of the lower portion of the receiver, where the fire is smothered. The same is true, of course, of any trash or litter which may be delivered to the machine or which may accumulate as the bean jackets burst.

Because of this technique, a very intense heat can be used without scorching the beans. The time of each exposure of an individual bean to the direct flame and the infra-red energy is, of course, determined by the peripheral velocity of the drum l8 and the total number of such exposures is determined by the degree of inclination of the drum axis and the receiver floor. The latter factor can be modified, for instance, by arranging the fins at any desired angle relative to the axis of the drum.

In one operative embodiment of the present invention, satisfactory results were achieved when using a drum 60 inches long and 9% inches in outside diameter, the fins being parallel with the drum axis, being equally spaced at 22% about the periphery of the drum and being three-fourths inch in radial extent, the drum being driven at rpm. and the delivery end of the drum being 1% inches lower than the inlet end of the drum.

The heat required for proper treatment of soybeans ranges from 250 to 300 BTU. per pound and is influenced by the temperature and the moisture content of the raw beans introduced to the apparatus. Some heat, of course, passes through the receiver into the room atmosphere; other heat escapes with the exhaust gases; but most of the heat supply is absorbed in the beans or is used in reducing their moisture content. The

tu 28.85/29.85) X1 0.9665 second unexposed 2. Time in apparatus 10 assuming 750 pounds per hour flow rate, net area of flow 36.5 square inches (cross sectional area of receiver 11 less cross sectional area of drum 18), drum length of 60 inches, and beans weighing 60 pounds per bushel or 35.8

cubic inches per pound:

Q 35.8 V: 12.25, inches per minute Where Q flow rate in cubic inches per minute T= L/V 60/ l 2.25 4.9 minutes in machine Where L length of drum 18 (60 inches) 3. Number of exposure of each bean:

N= TX RPMX 4.9 X 60= 294 exposures 4. Total time each bean exposed to flame:

Te= 294 X 0.0335 9.849 seconds 5. Total time each bean in apparatus and unexposed to flame:

Tu =294 x 0.9665 =284.151 seconds In FIG. 4, we have shown a slightly modified flame guard associated with the conduit 25. The bracket 33 and lip 35 are identical with those illustrated in FIG. 3, but a mating bracket 42 is formed with a lip 44 which is inclined somewhat inwardly with respect to the receiver in order to guard against the possibilityof the entry of beans through the slot 46.

In FIG. 5, we have somewhat diagrammatically illustrated a modified form of cooker. According to that figure, the receiver 51 is a trough having a lower, arcuate section 53 and an upper, straight-sided section 54, the upwardly-opening mouth of which is closed by a cover 55. In this form of the invention, the drum 58 is significantly smaller in diameter, relative to the radius of the receiver section 53, and the fins 60, therefore, have a significantly greater radial extent than do the fins 20 of the form of invention illustrated in FIGS. 1 and 2. Again, however, the axis 59 of the drum 58 is concentric with the arc of the section 53 of the receiver.

The burner 64 is in all respects similar to the burner 24, including flame guard means comprising cooperating lips 74 and 75 defining a slit 76 through which a flame 77 is directed toward, and preferably into impingement upon, the external surface of the drum The action of the form of the invention illustrated in FIG. 5 is in all respects analogous to that described above in connections with FIGS. 1 and 2, but we presently believe that the form of invention illustrated in FIGS. 1-3 is preferably in that it provides closer control of the application of the several kinds of heat to the beans because of the segregation of the beans into smaller groups.

Obviously, suitable controls for the constitution of the combustible mixture, the pressure under which it is supplied to the apparatus and the rotational velocity of the drum will be provided in order to facilitate the maintenance of optimum treatment conditions throughout the operation of the apparatus.

Our burner system has been used to treat raw corn. The results obtained by feeding the treated corn have been exceptionally good. These results were reported by the Cooperative Extension Service, Agricultural Experiment Station, Purdue University, Lafayette, Indiana on Mar. 26, 1970 at its annual Cattle Feeders Day Program. The Purdue report points out that the corn was treated by our machine disclosed herein until its temperature, at the exit end of the machine, was approximately 300 F. While raw corn weighs approximately 45 lbs. per cubic foot, the corn treated by Purdue in our machine weighed 39 lbs. per cubic foot, thus indicating an expansion of the corn in the heat treating process.

The Purdue experiment involved feeding 182 heifers averaging 510 lbs., initially. The heifers were divided into two lots of 91 each on Nov. 20, 1969. The data reported by Purdue were based on 112 days of experimenting. The heifers were fed a full feed of corn (raw for one lot and roasted or heat-treated for the other lot) which was ground and mixed with supplements in a ratio of 8 units ground shelled corn to 1 unit of supplement on an ad lib basis. The supplement was based on the following formula developed by Purdue: In 1,000

lb. mix, 1b.: Soybean meal, 640; molasses, 140; dehydrated alfalfa mean, 140; dicalcium phosphate, 52; iodized salt, 18; premix, l0 (10 million I. U. vitamin A, 5 gm. DES, 625 gm. zinc oxide, 2 gm. cobalt carbonate, 7 lb. soybean meal).

Medium quality hay was offered on a limited basis in order to provide minimum roughage.

The heifers which were fed the said mix including the roasted corn gained 14 percent more rapidly and required 10 percent less feed per pound of gain than those fed the mixture including regular, or, raw corn. These differences are reflected in lower total digestible nutrient (TDN) requirements and lower feed cost per pound of grain for those fed corn treated in our machine over those fed or untreated corn. Table I, below, illustrates these differences.

Table I Item Unit Raw Roasted com com No. heifers No. 91 9I Growth rate Wt. Nov. 20, 1969 lb. 509 SB Wt. March 12, 1970 lb. 770 811 Gain per heifer lb. 261 298 Daily gain lb. 2.33 2.66 Daily feed consumption Corn lb. 11.9 l2.4 Supplement lb. 1 .5 l .6 I-Iay lb. 2.4 2.4 Feed per pounds galn Corn lb. 512 468 Supplement lb. 64 58 Hay lb. WI 89 Dry feed per 100 lb. gain lb. 677 615 TDN per I00 lb. gain lb. 487 444 Feed cost per lb. gain l4.6 l4.0

Similar tests on corn treated in our machine have been made by Purdue using sheep as test animals. While the results of these last-mentioned tests have not yet been reported, they are believed to be even better results than those shown above.

We have conducted some tests in an attempt to establish control parameters for heat treating corn to obtain substantially the same characteristics achieved by Purdue. Our test data indicates that com can be treated in our machine at a rate of approximately 800 lb. per hour (or approximately 312 B.T.U. per lb.) to achieve an exit temperature of approximately 300 -320 F. The flame treatment time for the corn fed into our machine at a rate of 800 lb. per hour can be theoretically calculated using formulas provided above.

What is claimed is:

1. An apparatus for heat treating granular, organic materials comprising an elongated receiver having an inlet near one end and outlet near its other end, rotary means mounted in said receiver for turning about its own axis which extends longitudinally of said receiver, said rotary means including fins projecting outwardly relative to said axis, burner means including conduit means extending longitudinally of said receiver and provided with a longitudinally spaced plurality of ports opening toward the interior of said receiver, means for supplying a combustible mixture to said conduit means for ejection through said ports, and flame guard means disposed between said ports and said rotary means and constructed and arranged to define a laterallyrestricted, longitudinally extending slit through which the flaming combustible mixture ejected from said ports is directed to provide a wall of flame extending longitudinally and inwardly to said rotary means, and means for driving said rotary means, said fins being effective intermittently and rapidly to cascade granules disposed in said receiver through such a wall of flame and in close proximity to said flame guard means.

2. In combination with an elongated receiver supported with its length substantially horizontal and having an inlet near one end and an outlet near its other end, a drum mounted in said receiver for turning movement about its own axis which extends longitudinally of said receiver, longitudinally-extending fins on the external surface of said drum and projecting outwardly therefrom into close proximity to at least the lower portion of the internal wall of said receiver, and means for driving said drum, of burner means comprising conduit means extending longitudinally of said receiver adjacent the top of said receiver and provided with a longitudinally spaced plurality of ports opening toward the interior of saidreceiver, means for supplying a combustible mixture to said conduit means for ejection through said ports, and flame guard means disposed between said ports and said drum and constructed and arranged to define a restricted opening through which the flaming combustible mixture ejected from said ports is directed toward the external surface of said drum during turning movement of the latter.

3. The combination of claim 2 in which said flame guard means is effective to direct such flaming combustible mixture toward a peripherally-narrow, longitudinally-continuous region of said drum of continuouslychanging peripheral position during turning movement of said drum.

4. The combination of claim 3 in which such flaming combustible mixture impinges directly upon said peripherally-narrow region of said drum surface.

5. The combination of claim 2 in which such flaming combustible mixture impinges directly upon said drum surface.

6. The combination of claim 2 in which said flaming combustible mixture heats at least a portion of said flame guard means substantially to incandescence.

7. The combination of claim 1 in which said flaming combustible mixture heats at least a portion of said flame guard means substantially to incandescence.

8. The combination of claim 2 in which the axis of said drum and the floor of said receiver are inclined slightly downwardly from the inlet end toward the outlet end of said receiver.

9. The combination of claim 2 wherein the fins are substantially uniformly peripherally spaced and the radial extent of each fin is less than the peripheral spacing between fins.

10. The combination of claim 9 in which the angular spacing between fins is less than about 30.

11. The combination of claim 2 in which, in crosssection, the lower portion of the receiver is an arc concentric with the axis of said drum while the upper portion of the receiver is generally elliptical, whereby said fins cooperate with said receiver wall and said drum, when locatedin said lower portion of said receiver, to smother any flaming material disposed in said lower portion;

12. The combination of claim 2 in which said flame F8??? 55598122??? 182; fiistli ig s b ai 2.112% to define said restricted opening, that lip which extends in the direction of drum rotation being inclined inwardly.

13. An apparatus for heat treating granular, organic materials comprising a heat source including burner means with flame guard means, means for supplying a combustible mixture to said burner means to provide a flame projecting away from said burner means, said flame guard means being positioned with respect to said flame so as to be heated to incandescence by said flame and to provide a source of infra-red energy, and means for rapidly and intermittently cascading such materials through said flame and in close proximity to said flame guard means.

14. The apparatus of claim 13 in which said cascading means and said burner means are cooperatively positioned and arranged periodically to expose each such granule to said flame for a short period of time and to keep each such granule away from. said flame for a much longer period of time between each such exposure.

15. The apparatus of claim 13 in which said cascading means includes rotary means constructed and arranged generally spirally to move such granules longitudinally in the direction of its axis and about its axis, and in which said burner means is disposed adjacent said rotary means to project such a flame into the path through which such granules move.

16. The apparatus of claim 15 in which said burner means is elongated in the direction of said axis to project a laterally-narrow, longitudinally extending wall of flame into the generally spiral path through which such granules move.

17. The apparatus of claim 16 in which the cross section of said rotary means is such that the circumference of the generally spiral path through which each such granule moves is'many times greater than the lateral width of said wall of flame.

18. The apparatus'of claim 17 in which the circumference of the path is approximately 30 times greater than the lateral width of such a wall of flame.

, "UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,680,472 Dat d Auggst 1', 1972 Inizentofls) SI H Q g; g1. I

It is certified that error appears in the above-idemtified patent and that said Letters Patent are hereby corrected as shown below:

IN ABSTRACT Line 11 4 longitudinally spelled wrong IN SPECIFICATION Col. 2 line 8 delete "is" Col. 2 line 10 "received" should be "receiver" Col. 4 line 17 "three-fourths" is spelled out s rather than in numbers Col. 4 line 42 "te 1 29.8s should be Ut 1 H v v v Co1.*4 11m 43 "w ='2a.ss/29.8s)" shouldbe Col; 5 4 line 31 "connections" should be "Connection" Page 1.

ENITED STATES PATENT oFia CE CERTIFICATE OF CORRECTION Patent No. 3,689,472 Dated gust 1, 1972 Inventor(s) Skelton at 3.1. I

It is certified that error appears in the above-identified.patent and that said Letters Patent are hereby corrected as shown below:

Page

Col. 6 line 2 "mean" should be "meal" C01. 6 line 16 "fed" should be "fed raw" Col. 6 line 50 "ormu1as" should be "foirmu1ae" Signed and sealed this 22nd day of January 197E.

(SEAL) Attest:

EDWARD M. FLETCEER,JR. RENE D. 'I'EGTMEYER Attesting Officer Acting Commissioner of Patents FORM v 7 I USCOMM-DC 00376-P69 W U.S. GOVERNMENT PRINTING OFFICE III 0-3ll-3ll. 

1. An apparatus for heat treating granular, organic materials comprising an elongated receiver having an inlet near one end and outlet near its other end, rotary means mounted in said receiver for turning about its own axis which extends longitudinally of said receiver, said rotary means including fins projecting outwardly relative to said axis, burner means including conduit means extending longitudinally of said receiver and provided with a longitudinally spaced plurality of ports opening toward the interior of said receiver, means for supplying a combustible mixture to said conduit means for ejection through said ports, and flame guard means disposed between said ports and said rotary means and constructed and arranged to define a laterallyrestricted, longitudinally extending slit through which the flaming combustible mixture ejected from said ports is directed to provide a wall of flame extending longitudinally and inwardly to said rotary means, and means for driving said rotary means, said fins being effective intermittently and rapidly to cascade granules disposed in said receiver through such a wall of flame and in close proximity to said flame guard means.
 2. In combination with an elongated receiver supported with its length substantially horizontal and having an inlet near one end and an outlet near its other end, a drum mounted in said receiver for turning movement about its own axis which extends longitudinally of said receiver, longitudinally-extending fins on the external surface of said drum and projecting outwardly therefrom into close proximity to at least the lower portion of the internal wall of said receiver, and means for driving said drum, of burner means comprising conduit means extending longitudinally of said receiver adjacent the top of said receiver and provided with a longitudinally spaced plurality of ports opening toward the interior of said receiver, means for supplying a combustible mixture to said conduit means for ejection through said ports, and flame guard means disposed between said ports and said drum and constructed and arranged to define a restricted opening through which the flaming combustible mixture ejected from said ports is directed toward the external surface of said drum during turning movement of the latter.
 3. The combination of claim 2 in which said flame guard means is effective to direct such flaming combustible mixture toward a peripherally-narrow, longitudinally-continuous region of said drum of continuously-changing peripheral position during turning movement of said drum.
 4. The combination of claim 3 in which such flaming combustible mixture impinges directly upon said peripherally-narrow region of said drum surface.
 5. The combination of claim 2 in which such flaming combustible mixture impinges directly upon said drum surfacE.
 6. The combination of claim 2 in which said flaming combustible mixture heats at least a portion of said flame guard means substantially to incandescence.
 7. The combination of claim 1 in which said flaming combustible mixture heats at least a portion of said flame guard means substantially to incandescence.
 8. The combination of claim 2 in which the axis of said drum and the floor of said receiver are inclined slightly downwardly from the inlet end toward the outlet end of said receiver.
 9. The combination of claim 2 wherein the fins are substantially uniformly peripherally spaced and the radial extent of each fin is less than the peripheral spacing between fins.
 10. The combination of claim 9 in which the angular spacing between fins is less than about 30* .
 11. The combination of claim 2 in which, in cross-section, the lower portion of the receiver is an arc concentric with the axis of said drum while the upper portion of the receiver is generally elliptical, whereby said fins cooperate with said receiver wall and said drum, when located in said lower portion of said receiver, to smother any flaming material disposed in said lower portion.
 12. The combination of claim 2 in which said flame guard means comprises a pair of opposed lips extending toward each other with their distal edges spaced apart to define said restricted opening, that lip which extends in the direction of drum rotation being inclined inwardly.
 13. An apparatus for heat treating granular, organic materials comprising a heat source including burner means with flame guard means, means for supplying a combustible mixture to said burner means to provide a flame projecting away from said burner means, said flame guard means being positioned with respect to said flame so as to be heated to incandescence by said flame and to provide a source of infra-red energy, and means for rapidly and intermittently cascading such materials through said flame and in close proximity to said flame guard means.
 14. The apparatus of claim 13 in which said cascading means and said burner means are cooperatively positioned and arranged periodically to expose each such granule to said flame for a short period of time and to keep each such granule away from said flame for a much longer period of time between each such exposure.
 15. The apparatus of claim 13 in which said cascading means includes rotary means constructed and arranged generally spirally to move such granules longitudinally in the direction of its axis and about its axis, and in which said burner means is disposed adjacent said rotary means to project such a flame into the path through which such granules move.
 16. The apparatus of claim 15 in which said burner means is elongated in the direction of said axis to project a laterally-narrow, longitudinally extending wall of flame into the generally spiral path through which such granules move.
 17. The apparatus of claim 16 in which the cross section of said rotary means is such that the circumference of the generally spiral path through which each such granule moves is many times greater than the lateral width of said wall of flame.
 18. The apparatus of claim 17 in which the circumference of the path is approximately 30 times greater than the lateral width of such a wall of flame. 